UPSC Prelims 2018 · GS Paper I
Question 13: Geography
Which of the following has/have shrunk immensely/dried up in the recent past due to human activities ?
- 1.Aral Sea
- 2.Black Sea
- 3.Lake Baikal
Select the correct answer using the code given below :
AnswerUPSC’s answer is (a).
The Aral Sea, once among the world's largest lakes, has shrunk dramatically since the 1960s because the Amu Darya and Syr Darya, which fed it, were diverted to irrigate cotton and other crops in Central Asia. The Black Sea is a large open sea connected to the Mediterranean through the Bosphorus and has not dried up. Lake Baikal in Russia is the world's deepest freshwater lake and holds about a fifth of the world's surface fresh water. Remember: the Aral Sea is the textbook human-made disaster.
- 1. The Aral Sea shrank after the Amu Darya and Syr Darya were diverted for irrigation.
- 2. The Black Sea is a large open sea linked to the Mediterranean.
- 3. Lake Baikal is the deepest freshwater lake and has not dried up.
How you could have got this
- If you were sure statement 1 is correct, (b) and (c) go: each of them leaves 1 out.
What you needed to know: The Aral Sea shrank after the Amu Darya and Syr Darya were diverted for irrigation.
- Then, if you were sure statement 3 is not correct, (d) goes: it includes 3.
What you needed to know: Lake Baikal is the deepest freshwater lake and has not dried up.
Only (a) is left. You didn’t need statement 2.
Which options go is worked out from UPSC’s key and the options, not by a model.
Why each option is right or wrong
- (a) Right: only the Aral Sea has shrunk because of human diversion of its rivers.
- (b) Wrong: neither the Black Sea nor Lake Baikal has dried up.
- (c) Wrong: the Black Sea has not shrunk.
- (d) Wrong: Lake Baikal has not shrunk.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2018, General Studies Paper I, Series A. The paper on upsc.gov.in.